This invention relates generally to electrical connectors, and more particularly, to sealed electrical connectors having axially keyed components for positioning and retaining wires and contacts in a fixed position.
Connectors exist today that are mountable to the ends of various types of coaxial cables. In certain applications, the cables carry one or more differential signals. For instance, quad cables are used for conveying high-speed data communications. The quad cables include one pair of transmit lines and one pair of receive lines, all of which are twisted in a helix to maintain a desired orientation with respect to one another. When a connector is attached to a quad cable, it is preferable to maintain the transmit and receive lines in a fixed geometry. The transmit and receive lines are connected to transmit and receive contacts which are located in a particular relation to one another within the connector. In the event that the spacing between, or overall geometry of, the transmit and receive lines and/or contacts is disturbed from a preferred configuration, particular receive and/or transmit lines begin to interact electromagnetically with one another in a detrimental manner. For example, such detrimental electromagnetic interaction may cause degradation in the signal-to-noise ratio, impedance and the like, such as cross talk and/or electromagnetic interference.
One conventional quad connector includes a tubular shell having a hollow core configured to receive a one-piece or two-piece dielectric material that hold contacts connected to conductors of the quad cable. The contacts, the dielectrics, and the shell, have keying features which interlock with one another such that the contacts resist longitudinal movement along the length of the dielectric, and to prevent movement of the dielectric within the connector shell.
In certain applications, ingress of moisture, contaminants, and corrosive elements into the shell can undesirably influence the operation and reliability of the connector. It is therefore desirable to provide a sealed connector for these applications. The keying features of the connectors, however, can be an impediment to the use of conventional sealing elements. Known sealing elements are generally ineffective because moisture, contaminants, and corrosive elements may enter the connector assembly through the keyways and circumvent the seals of the connector.
Connectors are known which are permanently sealed to prevent moisture, contaminants, and corrosive elements from reaching the internal contacts of the connector. Such connectors are disadvantaged, however, in that they are not serviceable for repair. It would be desirable to provide a sealed connector in which, for example, damaged contacts could be accessed and replaced to repair the connector, rather than replacing the entire connector assembly. Sealing a connector which is intended to be disassembled and reassembled in such a manner has proven challenging.
In one aspect of the invention, a seal for an electrical connector in a connector block having a connector channel with a keyway is provided. The seal includes a tubular body that defines a longitudinal axis therethrough. The body includes a forward portion defining a forward end and a rearward portion defining a rearward end. The body is configured to be received in a connector channel in the connector block. A key portion extends longitudinally along an outer surface of the body. The key portion is configured to be received in the keyway in the connector channel. The body and the key portion seal the connector channel in the connector block when the connector is loaded into the connector block.
Optionally, the seal includes a plurality of circumferential sealing ribs formed on the outer surface. At least a portion of the sealing ribs extend from one side of the key portion to an opposite side of the key portion. The seal may be a sealing plug having a solid body; or, the seal may be a sealing boot wherein the body includes a passageway extending from the forward end to the rearward end. The passageway is configured to at least partially receive the electrical connector, and the body includes a plurality of circumferential interior sealing ribs on an interior surface of the passageway to seal an electrical cable extending therethrough.
In another aspect a connector assembly including a connector and sealing boot for a connector block having a connector channel including a keyway is provided. The assembly includes an outer connector shell having a cavity formed therein, and extending between a loading end and a mating end of the outer connector shell. A dielectric member holding contacts is received in the cavity. A sealing boot includes a tubular body defining a longitudinal axis and having a passageway extending therethrough. The body includes a key portion extending longitudinally on an outer surface thereof. The loading end of the outer connector shell is received in the passageway. The sealing boot is configured to seal the outer connector shell in the connector channel.
In yet another aspect, a sealed connector assembly is provided that includes a connector block including a mating end and a connector loading end. The connector block defines a plurality of connector channels, and each connector channel includes a keyway. Each of a plurality of connectors, is received in one of the connector channels. Each connector includes an outer connector shell having a mating end and a contact loading end. Each connector holds a plurality of contacts attached to a cable extending from the contact loading end. A sealing boot includes a tubular body defining a longitudinal axis and having a passageway extending therethrough. The contact loading end of the outer connector shell is received in the passageway. The body includes a key portion that extends longitudinally on an outer surface thereof. The key portion is received in the keyway of a respective one of the connector channels, such that the sealing boot seals the connector in the connector channel.
In certain applications, the signal wires 22 may be grouped into differential pairs and arranged in a particular geometry, such as a quadrature arrangement with a transmit pair 28 and a receive pair 30 as in the example of
The contacts 20 are each formed with a body section 32 having a pin 34 extending from a lead end 36 thereof. Each body section 32 has a larger diameter than the diameter of the corresponding pin 34 in order to define a flared section 38 therebetween. The body section 32 includes a raised surface defined by a front facing shoulder 40 and a rear facing shoulder 42. The flared section 38 and the shoulders 40 and 42 may be sloped or step-wise. Each body section 32 further includes a wire barrel 44 formed thereon and extending opposite to the pin 34. The wire barrel 44 is hollow and configured to receive the conductors of a corresponding signal wire 22. The wire barrels 44 may be affixed to corresponding signal wires 22 in a known manner, such as soldering, crimping, or insulation displacement and the like. Further, in alternative embodiments, the contacts 20 may include socket contacts or other well-known contact types.
The ferrule 16 includes an opening 46 extending therethrough and a rim 48 at a rear end 50 of the ferrule 16. The ferrule 16 is inserted over the contacts 20 until resting upon the cable 24. The ferrule 16 includes an exterior wall 52 that is dimensioned to be received within the braid 26 and to sandwich the braid 26 between the ferrule 16 and the outer shell 12 with the rim 48 proximate a loading end 54 of the outer shell 12.
The outer shell 12 is generally tubular in shape and is formed with a mating end 56 configured to be joined with a corresponding mating connector assembly, such as a socket connector assembly (not shown). The outer shell 12 includes a cavity 58 extending therethrough between the loading and mating ends 54 and 56. The outer shell 12 includes a lead portion 60 dimensioned to be received within the mating connector assembly. A rim 62 is provided at an interface between the lead portion 60 and a body portion 64. A positioning key 63 is formed on the rim 62. The body portion 64 includes a dimple 66 formed along the length of the body portion 64, thereby defining a keying feature that projects into the cavity 58. The dimple 66 extends in a direction parallel to a longitudinal axis 68 of the connector assembly 10 (also referred to as the center line of the outer shell 12).
The dielectric member 14 may be a unitary structure formed from a single piece of insulative material, or in alternative embodiments, may be a two piece structure. The dielectric member 14 includes front and rear ends 70 and 72 oriented along the longitudinal axis 68. A plurality of contact passages 74 are formed within the dielectric member 14 and extend between the front and rear ends 70 and 72. The contact passages 74 are formed in a predefined geometry relative to the longitudinal axis 68 of the connector assembly 10 based on the particular application and geometry of the cable 24. A keying notch 76 is formed in the exterior of the dielectric member 14 and extends rearward from the front end 70. The keying notch 76 is shaped to register with the dimple 66 projecting into the cavity 58 to orient and align the dielectric member 14 with respect to the outer shell 12. The dielectric member 14 includes a lead section 78 having a smaller diameter than an intermediate body section 80. The lead section 78 extends into the lead portion of the cavity 58 within the lead portion 60 of the outer shell 12. A rim 82 is formed on the dielectric member 14 at the interface between the lead and body sections 78 and 80, which locates the dielectric member 14 at a predetermined depth within the outer shell 12 from the mating end 56 along the longitudinal axis 68.
The dielectric member 14 also includes a flared section 84 (also referred to as a contact gripping section) formed proximate the rear end 72. The flared section 84 has an outer envelope with a larger diameter proximate the rear end 72 than the diameter of the body section 80. In the example of
The dielectric member 14 further includes a plurality of collets 88 cut or formed therein and extending from the rear end 72 forward in a direction parallel to the longitudinal axis 68. Optionally, the collets 88 may be cut or formed in a pie or spiral pattern with respect to the longitudinal axis 68, and extending along the dielectric member 14. The collets 88 in the example of
Assembly of the connector 10 is accomplished after the cable 24 is inserted through the passageway 112 of the seal 18 from the rearward end 110. The contacts 20 are then further inserted into the dielectric member 14 along the longitudinal axis 68 until the contacts 20 are in a loaded position. To insert the dielectric member 14 into the outer shell 12, the keying notch 76 of the dielectric member 14 is visually aligned with the dimple 66 of the outer shell 12, and the dielectric member 14 is inserted into the loading end 54 of the outer shell 12. Once loaded, the connector assembly 10 is assembled and the connector assembly 10 may be secured by a crimping process, such as, for example, a hex-crimp process or an O-crimp process.
The seal 18 includes a tubular body 100 that extends along a longitudinal axis 102 that is coincident with the connector axis 68. The body 100 includes a forward portion 104 defining a forward end 106 and a rearward portion 108 defining a rearward end 110. In the embodiment of
The passageway 112 includes a forward cylindrical chamber 132 having a diameter D1 and a rearward cylindrical chamber 134 having a diameter D2 that is than less D1. The forward chamber 132 is configured to receive at least part of the body portion 64 of the connector outer shell 12. The rearward chamber 134 is sized to receive the cable 24 and includes a plurality of circumferential interior sealing ribs 136 formed on an interior surface 138 of the rear chamber 134. The interior sealing ribs 136 provide sealing to prevent the rear entry of contaminants into the connector assembly 10 from around the cable 24. The sealing boot may be fabricated from rubber or other known elastic materials commonly used for sealing purposes. The material may or may not be self lubricating.
The backshells 184 and 186 are identical to one another but are inverted relative to one another when installed on the connector block 182. The backshells 184 and 186 each includes fasteners 200 for attachment of the backshells 184 and 186 to the connector block 182. In one embodiment, the fasteners 200 are threaded and may include captive screws. Each backshell 184 and 186 also includes cable guides 202 to organize the cables 24 at the connector receiving end 194 of the connector block 182. A cable tie 204 retains the cables 24 in the cable guides 202.
Each backshell 184 and 186 also includes a strain relief member 206 located proximate a forward face 208 of the backshells 184 and 186. The strain relief member 206, in one embodiment, is bonded to the backshells 184 and 186. In alternative embodiments, the strain relief member 206 may be formed integrally with the backshells 184 and 186. When the backshells 184 and 186 are fastened to the connector block 182, the strain relief member 206 engages rearward ends 110 and 150 of the seals 18 and plugs 140, respectively, to impart a forwardly directed load in the direction of arrow A that compresses the sealing boots 18 and the sealing plugs 140 longitudinally within the connector channels 196. The longitudinal compression causes a radial expansion of the sealing boots and the sealing plugs 18 and 140, respectively, within the connector channels 196 to enhance the sealing of the connector channels 196. In one embodiment, a sealing gasket 210 is positioned between the connector block 182 and each backshell 184 and 186. In other embodiments, the sealing gasket 210 may not be present.
In use, the assembled connectors 10 are loaded into the connector block 182 from the connector receiving end 194. The connectors 10 are oriented such that the positioning keys 63 are received in keyways (not shown) in the connector channels 196 of the connector block 182. The key portion 118 of the sealing boots 18 are then aligned with the positioning keys 63 and the keyways in the connector channels 196 and inserted into the connector channels 196 and over the rearward portion 64 (
Each of the sealing ribs 420 includes a key portion 426 formed thereon. The key portion 426 is configured to be received in the keyway of a keyed connector channel (not shown). As shown in
The above-described embodiments provide a cost effective and reliable sealing boot 18 for a connector assembly 10. Specifically, the connector assembly 10 includes an outer shell 12 having a positioning key 63 that is used to orient the connector assembly 10 in a connector channel having a keyway in a connector block 182. The sealing boot 18 includes a key portion 118 that is configured to be received in the keyway and a plurality of circumferential sealing ribs 120 on the outer body 100 of the sealing boot 18. The sealing ribs 120 and the key portion 118 cooperate to seal the irregularly shaped keyed connector channel 196. A passageway 112 extends through the sealing boot 18 to receive a rearward portion 64 of the connector assembly 10 and a cable 24 to which the connector assembly 10 is attached. Interior sealing ribs 136 on the interior of the passageway 112 provide sealing between the cable 24 and the sealing boot 18. A strain relief member 206 compresses the sealing boot 18 longitudinally to expand the sealing boot 18 radially to improve the pressure of the sealing boot 18 against the connector channel walls. A solid sealing plug 140 is provided to seal unused connector channels 196 in the connector block 182.
Exemplary embodiments of a sealing boot 18, 400 and a sealing plug 140 for keyed connector applications are described above in detail. The sealing boot 18, 400 and sealing plug 140 are not limited to the specific embodiments described herein, but rather, may include variations consistent with the basic component designs. For example, the sealing boot 18, 400 and sealing plug 140 may include sealing ribs 120, 160, 420 along the full length of the sealing boot and plug bodies 100, 142, 402. Likewise, the key portions 118, 156, 426 of the sealing boot 18, 400 and sealing plug 140 may also extend the full length of the sealing boot and plug bodies 100, 142, 402.
While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.